On Demand Liquid Metal Programming for Composite Property Tuning

Soft electronics have become increasingly necessary for the implementation and integration of novel technologies in a variety of environments including aerospace, robotics, and healthcare. In order to develop these soft electronic devices, materials and manufacturing strategies are required for these soft, stretchable, and flexible systems. Further, the ability to effectively tune not only these mechanical properties but also their thermal and electrical properties is key to developing multifunctional materials for soft electronic applications. In this thesis, we present a method of printing highly tunable flexible and stretchable composites consisting of elastomers with liquid metal (LM) inclusions. We analyze the mechanical and functional behaviors and highlight the anisotropic properties that can be created via our printing system, and we apply this understanding to the development of a multiphase material with a programmable crack propagation path. Throughout this work we describe the process by which we use Direct Ink Write (DIW) technology, a type of additive manufacturing, to print 2D and 3D LM composites with tunable properties. The design map used to control LM microstructure in-situ is first outlined in Chapter 2. This tuning ability is used to print materials with varied LM microstructures and study the impact on mechanical, thermal, and electrical properties (Chapter 2, Chapter 3). We further study the elongated LM droplet inclusions for how their orientation with respect to loading may impact mechanical properties (Chapter 3). We further utilize these findings to control crack propagation along a specified path using only variations in printing parameters (Chapter 3). We provide concluding statements and outlooks on future work in Chapter 4. We then summarize our findings and detail the implications for the soft electronics field (Chapter 5).

Name thesis:degree_name

Master of Science

Level thesis:degree_level

masters

Discipline thesis:degree_discipline

Mechanical Engineering

Department dc:contributor.department

Mechanical Engineering

Grantor dc:publisher

Virginia Tech

Year dc:date.issued

2023

Author dc:creator

• Schloer, Gwyneth Marie

Chair dc:contributor.committeechair

• Bartlett, Michael David

Committee members dc:contributor.committeemember

• Behkam, Bahareh
• Williams, Christopher Bryant

• liquid metal
• soft electronics
• additive manufacturing

Statement dc:rights

• In Copyright

Licence dc:rights.uri

• http://rightsstatements.org/vocab/InC/1.0/

Language dc:language.iso

en

Dc Identifier Other

vt_gsexam:37453

OAI identifier oai:identifier

oai:vtechworks.lib.vt.edu:10919/115554